Hi,
I've written an export plugin that exports all or all selected objects to the GLBasic .ddd file format. You can download the source code and the windows plugin from here:
http://www.GLBasic.com/files/ac3d-ddd-plugin.zip
More information about GLBasic on
www.GLBasic.com.
AC3D rocks! It was so easy to write an export plugin, I woudn't believe it myself if I hadn't done it.